Six Ukrainian servicemen were ambushed and killed and eight others wounded Tuesday afternoon outside the town of Kramatorsk, the defense ministry said. They were attacked by at least 30 insurgents using grenade launchers and automatic weapons, it said in a statement.
Kramatorsk is in the Donetsk region, one of two in eastern Ukraine that declared independence on Monday.
Speaking at Kiev's main airport, German envoy Frank-Walter Steinmeier said he came to support efforts to arrange a dialogue between Ukraine's central government in Kiev and its pro-Russia opponents in the Donetsk and Luhansk regions that form the nation's eastern industrial heartland. Pro-Russia insurgents in those regions have seized government buildings and clashed with government forces for the past month.
Steinmeier's trip is part of the road map for settling Ukraine's crisis laid out by the Organization for Security and Cooperation in Europe, a trans-Atlantic security group.
The OSCE plan calls on all sides to refrain from violence and urges amnesty for those involved in the unrest as well as talks on decentralization and the status of the Russian language. It envisages a quick launch of high-level round tables across the country bringing together national lawmakers and representatives of the central government and the regions.
But Ukrainian officials sounded skeptical Tuesday about the OSCE plan.
Speaking in Brussels, acting Prime Minister Arseniy Yatsenyuk thanked the Vienna-based OSCE but said Ukraine has drawn up its own "road map" for ending the crisis and noted the people of his country should settle the issue themselves.
Russia, meanwhile, called Tuesday for a swift implementation of the OSCE plan, saying its demand to end violence means that Kiev should stop its military operation to recapture buildings in the east, lift its blockade of cities and towns, pull its forces from eastern regions and release all insurgents.
"We are demanding (they) stop intimidating civilians by using force or threatening to use it," Russia's Foreign Ministry said in a statement.
It added that it expects separatists in Ukraine's Donetsk and Luhansk regions to respond in kind if Kiev does.
Russia also urged the United States and the European Union to persuade authorities in Kiev to prioritize discussions of giving more powers to Ukraine's regions ahead of the country's May 25 presidential vote.
Yevhen Perebiynis, spokesman for the Ukrainian foreign ministry, lamented Tuesday that the OSCE deal does not specifically oblige Russia to do anything. The Ukrainian government and the West have accused Russia of fomenting the mutiny in the east to derail Ukraine's presidential vote and possibly grab more land.
"The de-escalation of the situation directly depends on whether Russia will stop sponsoring the terrorists, withdraw its troops from the border or whether it will call on terrorists lay down the arms and vacate the building they have seized," Perebiynis said in comments carried by the Interfax Ukraine news agency.
The separatists held a referendum Sunday and claimed that about 90 percent of those who voted in Donetsk and Luhansk backed sovereignty. The two regions declared independence on Monday and those in Donetsk even asked to join Russia.
Ukraine's acting president called the vote a sham and Western governments said it violated international law.
The Kremlin has shown no immediate intention of annexing eastern Ukraine like it did the strategic Crimean Peninsula in March. Instead, Moscow has pushed for talks between Ukraine's central government and eastern regions on Ukraine's future — suggesting that Russia prefers a political rather than a military solution to its worst standoff with the West since the Cold War.
The interim government in Kiev had been hoping the May 25 presidential vote would unify the country behind a new, democratically chosen leadership. But Ukraine's crisis could grow even worse if regions start rejecting the presidential election. The insurgents in Luhansk have already said they wouldn't hold the presidential vote.
Serhiy Taruta, the Kiev-appointed governor of the Donetsk region, on Tuesday urged the Ukrainian parliament to authorize a June 15 vote to help the regions gain more powers while still remaining part of Ukraine.
While he dismissed Sunday's separatist vote as an "opinion poll," Taruta said everyone in Ukraine, including those in the rebellious east, "should hear answers to the questions that they are concerned about."
Taruta said key issues include devolving more powers to local authorities, creating municipal police forces and approving a broader use of languages other than Ukrainian.
Insurgents, meanwhile, said unidentified assailants fired at a car carrying Valery Bolotov, a separatist leader in Luhansk. Bolotov was hospitalized with wounds but they were not life-threatening, the insurgents said. Bolotov was the one who announced independence Monday for his region.
Vladimir Isachenkov in Moscow, Peter Leonard in Donetsk and John-Thor Dahlburg in Brussels contributed to this report.
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